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The size-weight illusion in 2-D nonlinear psychophysics
1Department of Psychology, University of New England, Armidale, N.S.W., Australia.
Perception & Psychophysics
|October 1, 1990
Summary
This study introduces nonlinear cross-coupling in psychophysics to explain perceptual phenomena like the size-weight illusion. It suggests these illusions arise naturally from sensory dimension interactions, not just errors.
Area of Science:
- Psychophysics
- Perception science
- Sensory integration
Background:
- Unidimensional nonlinear psychophysics models perceptual phenomena.
- Cross-coupling between parameters of single-channel recursions has been previously established.
Purpose of the Study:
- To extend unidimensional nonlinear psychophysics by incorporating cross-coupling.
- To investigate the role of nonlinear cross-coupling in perceptual illusions, specifically the size-weight illusion.
Main Methods:
- Postulating forms of cross-coupling between parameters of two single-channel recursions.
- Analyzing the topology of relations to reproduce the size-weight illusion.
Main Results:
- The size-weight illusion is reproducible within the proposed framework of nonlinear cross-coupling.
- Conditions producing the illusion involve partially compensating cross-coupling of sensory dimensions.
Conclusions:
- So-called perceptual illusions may be natural consequences of nonlinear cross-coupling in sensory processing.
- A second equilibrium state, characterized by no cross-coupling and resembling veridical perception, exists in some subjects.
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